Ecological Entomology (2011) 36, 231-240

Peter M.J. Brown, Robert Frost, Julian Doberski, Tim Sparks, Richard Harrington and Helen E. Roy (2011)
Decline in native ladybirds in response to the arrival of Harmonia axyridis: early evidence from England
Ecological Entomology 36 (2), 231-240
Abstract: 1. Harmonia axyridis (Coleoptera: Coccinellidae) is an invasive non-native ladybird in Europe, where it was introduced as a biological control agent of aphids and coccids.
2. This study assesses changes to ladybird species assemblages, in arboreal habitats, over a 3-year period encompassing the invasion phase of H. axyridis in eastern England. The effects of H. axyridis and other factors (weather and prey availability) on native ladybirds are assessed.
3. Harmonia axyridis increased from 0.1% to 40% of total ladybirds sampled, whilst native aphidophagous species declined from 84% to 41% of total ladybirds. The actual number of native aphidophagous ladybirds per survey decreased from a mean of 19.7 in year 1, to 10.2 in year 3.
4. Three ladybird species in particular experienced declines: Adalia bipunctata, Coccinella septempunctata, and Propylea quatuordecimpunctata. Harmonia axyridis was the most abundant species by the end of the study.
5. The decline in native aphidophagous ladybirds could be attributed to competition for prey and intraguild predation of eggs, larvae, and pupae by H. axyridis. Physiological and behavioural traits of H. axyridis are likely to confer an advantage over native ladybird species.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Peter Michael James Brown, Helen Elizabeth Roy, Richard Harrington

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
environment/habitat manipulation

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
Adalia bipunctata (predator)			United Kingdom
Coccinella septempunctata (predator)			United Kingdom
Harmonia axyridis (predator)			United Kingdom
Propylea quatuordecimpunctata (predator)			United Kingdom